A build-up of electrical charges, known as "static electricity", can discharge suddenly and cause undesirable sparking particularly in rolled up articles such as adhesive tapes and sheets. It is known in the art that antistatic materials can avoid or compensate for the build-up of static electricity.
There is a growing interest in the use of antistatic materials and coatings in various fields of technology, particularly in the electronics industry. For example, in electronics manufacturing, electrostatic discharge can result in expensive and difficult to detect damage to electronic components. Build-up of electrical charges can also result in difficulties in handling and attraction of dust and debris.
Adhesive tapes, particularly pressure sensitive adhesive tapes, are useful in electronics manufacturing, for example in masking and packaging applications. Tape handling (e.g., unwinding) can result in the generation of very high electrostatic charges which are greatly in excess of that required to damage typical electronic components. Before such pressure sensitive adhesive tapes are brought into contact with electronic components, as in, for example, a masking operation, the electrostatic charge on the tape must be removed. Conventionally this is done by the action of ionized air on the tape. Frequently, however, this is only a temporary solution.
Various materials have been suggested for use as an antistatic layer. For example, vanadium oxide dispersions have been reported to be effective antistatic layers in photographic constructions. Additionally, aqueous copolyester dispersions which contain ionic antistatic agents, such as monosodium salt of vanadic acid, have been reported as useful with photographic media.